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Discussion Starter #1
After 70mph, front end feels very light-footed, and seems to wander a bit.
I find myself holding on tightly with both hands, and slowing down.
1971 240Z, 5spd, 16x8’s, new 205 Bridgestone tires. Shocks/springs
have approximately 3,000mi. New sway bar end links. ??
Any suggestions? Thank you!
 

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16" rims? Sounds like it could be aerodynamic lift if the front end is raised and more air going under car.
 

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After 70mph, front end feels very light-footed, and seems to wander a bit.
I find myself holding on tightly with both hands, and slowing down.
1971 240Z, 5spd, 16x8’s, new 205 Bridgestone tires. Shocks/springs
have approximately 3,000mi. New sway bar end links. ??
Any suggestions? Thank you!
Check the normal things. Worn parts, rack bushings, alignment especially toe in. These cars get light in the front at high speeds. But not 70. Usually above 90.
 

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Discussion Starter #5
@dumbestone, yes they are 16” wheels, but tire diameter is identical to factory 14”. Car sits no higher than stock, but I would like to lower it, as I too believe too much air may be the problem. It doesn’t feel mechanical. Since I plan to lower it, I was waiting to do alignment.
 

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The Z has always been a bit 'light' in the front end at speed. Therefore the front air dams and 'spooks' from BRE. What was real interesting back in the day was guys putting the rear spoiler on first and NO front spoiler. I remember a few guys who related their 'white knuckle' experience over a couple beers. Then they IMMEDIATELY ordered a 'spook' or similar.
 

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Did you try to wiggle the tires to see if there is any play or did you just look at the components? I'd give the tires a shake in a variety of directions and let us know.
 

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Discussion Starter #14
I will take your suggestion, and try to wiggle the tires. I assume that would be done with the tires off the ground correct?
I was going through the receipts I got with the car, the whole front looks like it was done in 2004, which sounds like a long time ago. However after the car was restored it went into a museum and has only been driven two thousand miles since. The front end rebuild consisted of new strut cartridges lower ball joints, inner and outer tie rods, and control arm bushings. At that time they also replaced the rear lower control arm bushings rear lower outer control arm bushings, and a spindle link whatever that is. Thanks again, for all your help!
 

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Back in the day I autocrossed my Z S30 put lots of wear & tear on front end - tie ends & ball joints.Disconnect outer tie rod and check how loose it is: should be some resistance and return to center, push/pull to check looseness of inner. Wider tires put bit of extra load - contact patch tire to road bigger. Strut cartridge try autocross or road racing recommended to control small movements - old style specs for cartridge used to list compression and rebound numbers but gone in new age. Low cost cartridge may have trouble handling movements at speed. Strut tower mounting h/w rubber and bearing. Old strut rubber gets hard and looses ability to moderate minor movement. Repack/replace wheel bearing. START wish list for components as part of lowering Z.

Ran stagger 225 / 14" front and 235-265 / 14" rear and like you compensated for outer tire diameter and offset. Energy Suspension tension rod rubber - rear kit. Stiffer springs all around. Replaced some components frequently(ball joints, wheel bearing). For me wear & tear drove component repair and NOT mileage or age.

Repeat suggestion for air dam.

I enjoy repairing (wrenching) my Z - 1977 280Z and 2003 350Z.
 

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Discussion Starter #16
I hear you on the BRE type front spoiler, and don’t doubt that it would help, but I just do not care for the look.
@spd350z, besides springs, and shocks, what else would your wish list include when doing, front and rear, if you going through the effort to lower the ride height?
 

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Before worrying about all the condition of the parts in your front end, you need to take care of the lift in the front end. It's the same on all z cars and it's severe. The cars wander at 60 and above, trucks, buses, and cross winds blow you all over the road and they hydroplane easy on wet roads. Starts getting lift at 35 mph, you just don't notice it until 60 and it's a constant course correction. At 90 and above they get power steering. You're driving an airplane wing down the road. You may not like the looks of a BRE chin spoiler but they do work pretty good. Your best bet though is a xenon air dam. They provide even more stability in the front end at 60 than the BRE spoiler and reach maximum efficiency at 90 and above. They eliminate the lift in the nose period. They don't blow up when you hit something like the chin spoiler does, because the xenon unit is made out of urethane. The lip you have on your car now isn't doing hardly anything to help counteract the lift. Z man of Washington.
 

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